The invention relates to a mechanism for queuing calls. U.S. Pat. No. 6,259,786 to Doug Gisby discloses a call queuing system for a call centre. The call queuing system establishes virtual calls for callers. As used in the '786 patent, a virtual queue environment means a system in which callers may disconnect from the call centre without losing their place in a queue, and still be served in the order they originally held in queue. The call queuing system allows the callers to disconnect and await a later callback when the virtual call is routed to an agent. An agent is the person, such as an expert, who ultimately takes the call. Callers are connected to an Interactive Voice Response unit (IVR) and informed that they may disconnect and await the callback. An IVR may also be used when the callback is made, informing the caller of the nature of the new call, and that they are now being connected to an agent.
A problem associated with the '786 patent is that all agents, ie, the experts who ultimately answer the calls, are assumed omniscient. In other words, each agent must be able to process a call from any caller. In some applications this is an unreasonable requirement. If the call is routed to an agent who is not able to answer the caller's question, the caller has queued in vain.